mkaravel commented on code in PR #52316: URL: https://github.com/apache/spark/pull/52316#discussion_r2347027423
########## sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/aggregate/datasketchesAggregates.scala: ########## @@ -146,8 +151,11 @@ case class HllSketchAgg( case IntegerType => sketch.update(v.asInstanceOf[Int]) case LongType => sketch.update(v.asInstanceOf[Long]) case st: StringType => - val cKey = CollationFactory.getCollationKey(v.asInstanceOf[UTF8String], st.collationId) - sketch.update(cKey.toString) + val str = v.asInstanceOf[UTF8String] + if (str != null && str.numBytes > 0) { + val cKey = CollationFactory.getCollationKeyBytes(str, st.collationId) + sketch.update(cKey) + } Review Comment: It might be helpful to look at the `buildCollation` method: https://github.com/apache/spark/blob/master/common/unsafe/src/main/java/org/apache/spark/sql/catalyst/util/CollationFactory.java#L589 This is where the `sortKeyFunction` is set. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org